19 ms·

Some say concrete should be replaced wholesale with wood (CLT). I imagine that would make a dent?

by brnt 4y ago

jjk166 4y ago
Every year humans use approximately 9 Billion tons of concrete. The mass of 12 Trillion trees is approximately 1100 years worth of concrete. This much lumber would need to be used every 200 years or so.
- runarberg 4y ago
  I see, so we are never going to be able to use trees to capture our current current CO2 emissions. However would it be possible to use trees (and other photosynthetic organisms) to capture our historic emissions in a mass global atmospheric cleanup efforts, after we’ve mostly gone carbon neutral? Or is that also like a 1000 year effort even if we became carbon neutral tomorrow?
  - jjk166 4y ago
    If we stopped emmitting CO2 tomorrow, a realistic increase in number of trees (~1 trillion trees) would take about 900 years to return to pre-industrial co2 levels. The more trees you plant, the faster it goes, but even if you cover the entire planet in forest (including places like Antarctica and the Sahara), you're still looking at centuries. Other organisms can be used as well, but again you need to sequester the carbon.
    - runarberg 4y ago
      Thanks. I appreciate your answers here. This is why I love HN. Getting answers to questions on niche topics I don’t even know how to begin searching for.
  - r_hoods_ghost 4y ago
    Pretty much. I don't have the numbers but the phrase to always bear in mind is "fossil carbon." All that oil, gas and coal was once living bio matter (to a first approximation). Industrial civilisation has been predicated on us burning fossil carbon laid down over millions of years by earths organisms. It will take more than a few decades to remove the excess that we have pumped in, even if we reforest the earth, reduce the population and all become ascetics.
ninju 4y ago
Of course the creation of concrete has its own environmental impact https://psci.princeton.edu/tips/2020/11/3/cement-and-concrete-the-environmental-impact https://psci.princeton.edu/tips/2020/11/3/cement-and-concret...

Some say concrete should be replaced wholesale with wood (CLT). I imagine that would make a dent?

by brnt 4y ago

Some say concrete should be replaced wholesale with wood (CLT). I imagine that would make a dent?

Every year humans use approximately 9 Billion tons of concrete. The mass of 12 Trillion trees is approximately 1100 years worth of concrete. This much lumber would need to be used every 200 years or so.

runarberg 4y ago
I see, so we are never going to be able to use trees to capture our current current CO2 emissions. However would it be possible to use trees (and other photosynthetic organisms) to capture our historic emissions in a mass global atmospheric cleanup efforts, after we’ve mostly gone carbon neutral? Or is that also like a 1000 year effort even if we became carbon neutral tomorrow?
- jjk166 4y ago
  If we stopped emmitting CO2 tomorrow, a realistic increase in number of trees (~1 trillion trees) would take about 900 years to return to pre-industrial co2 levels. The more trees you plant, the faster it goes, but even if you cover the entire planet in forest (including places like Antarctica and the Sahara), you're still looking at centuries. Other organisms can be used as well, but again you need to sequester the carbon.
  - runarberg 4y ago
    Thanks. I appreciate your answers here. This is why I love HN. Getting answers to questions on niche topics I don’t even know how to begin searching for.
- r_hoods_ghost 4y ago
  Pretty much. I don't have the numbers but the phrase to always bear in mind is "fossil carbon." All that oil, gas and coal was once living bio matter (to a first approximation). Industrial civilisation has been predicated on us burning fossil carbon laid down over millions of years by earths organisms. It will take more than a few decades to remove the excess that we have pumped in, even if we reforest the earth, reduce the population and all become ascetics.

ninju 4y ago

Of course the creation of concrete has its own environmental impact https://psci.princeton.edu/tips/2020/11/3/cement-and-concrete-the-environmental-impact https://psci.princeton.edu/tips/2020/11/3/cement-and-concret...